NUS Environmental Research Institute, National University of Singapore, 5A Engineering Drive 1, #02-01, Singapore 117411, Singapore; Department of Civil and Environmental Engineering, National University of Singapore, Kent Ridge Crescent, Singapore 119260, Singapore; School of Environment, Harbin Institute of Technology, Harbin 150090, PR China.
NUS Environmental Research Institute, National University of Singapore, 5A Engineering Drive 1, #02-01, Singapore 117411, Singapore.
J Colloid Interface Sci. 2022 Oct 15;624:691-703. doi: 10.1016/j.jcis.2022.05.152. Epub 2022 May 30.
The ecological and environmental problem caused by harmful algal blooms (HABs) is challenging to humans. The simultaneous elimination of cyanobacteria and phosphate from eutrophic waters is of great importance. Herein, a new lanthanum peroxide-loaded sepiolite nanocomposite was fabricated via a facile in-situ co-precipitation method and demonstrated the excellent properties on removal of phosphate and inhibition of cyanobacteria growth. The optimized nanocomposite (termed as LPS30) prepared with a La-to-Sepiolite mass ratio of 0.3:1 demonstrated the best cyanobacteria removal with an effective duration of at least 3 months, due to the even dispersion of high-content LP nanoparticles in the sepiolite. LPS30 exhibited a high phosphate uptake (52.68 mg-P/g), fast uptake kinetics (∼45 min to reach 80% of ultimate uptake), and relatively higher selectivity in the presence of competing matters. The pH-dependent phosphate sorption resulted from the ligand exchange between phosphate and surface functional groups (e.g., peroxo and hydroxyls), and the electrostatic attraction. The efficient and long-lasting inhibition for cyanobacteria regrowth was attributed to the combined effect of the oxidative species (i.e., LaOO-) and the efficient removal of phosphate through the coagulation flocs. Our study demonstrated that LPS30 is a promising material to simultaneously treat phosphate and algae for HABs management.
有害藻类水华（HABs）引起的生态和环境问题对人类具有挑战性。同时从富营养化水中去除蓝藻和磷酸盐非常重要。本文通过简便的原位共沉淀法制备了一种新型负载过氧化镧的海泡石纳米复合材料，该复合材料在去除磷酸盐和抑制蓝藻生长方面表现出优异的性能。通过La 与海泡石的质量比为 0.3:1 优化的纳米复合材料（称为 LPS30）具有最佳的蓝藻去除效果，有效时间至少为 3 个月，这是由于高含量 LP 纳米颗粒在海泡石中的均匀分散。LPS30 具有较高的磷吸收量（52.68 mg-P/g）、较快的吸收动力学（~45 分钟即可达到 80%的最终吸收量），并且在存在竞争物质时具有相对较高的选择性。磷的吸附与 pH 值有关，这是由于磷与表面官能团（如过氧和羟基）之间的配体交换以及静电吸引。对蓝藻再生的高效且持久的抑制作用归因于氧化物种（即 LaOO-）的综合作用以及通过凝聚絮体有效去除磷酸盐。本研究表明，LPS30 是一种同时处理 HABs 管理中磷酸盐和藻类的有前途的材料。
